OUTLINE: This is a randomized, open-label, multicenter study. Patients are randomized to 1 of 3 treatment arms. Arm I: Patients receive ZD9331 IV over 30 minutes on days 1 and 8. Arm II: Patients receive a higher dose of ZD9331 IV over 30 minutes on days 1 and 8. Arm III: Patients receive ZD9331 as in arm I and topotecan IV over 30 minutes on days 1-5. All arms: Treatment repeats every 21 days in the absence of disease progression or unacceptable toxicity. Quality of life is assessed at baseline, on the first day of each course, and then at study withdrawal. Patients are followed at day 30, every 9 weeks until disease progression, and then every 6 months thereafter.